﻿<p>The <em>IfcSpecularRoughness</em> defines the datatype for the reflection resulting from the roughness of a surface through the height of surface impurities where the specular highlight is made sharper with small values for the roughness, such as 0.1. Applies to "glass", "metal", "mirror" and "plastic" reflection models. Larger values, close to 1.0 decrease the specular fall-off.</p> 

<p><em>IfcSpecularRoughness</em> is of type REAL. It is constraint to values between (and including) 0 and 1.</p>

<blockquote class="note">
NOTE&nbsp; The datatype relates to the definition of "shiness" in <a href="../../../bibliography.htm#IEC-14772-1">ISO/IEC 14772-1</a>, which is the reciprocate value to the specular roughness.
</blockquote> 

<blockquote class="history"> 
HISTORY&nbsp; New type in  IFC2x2.
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